MAKHNEI, O.V.; PYLYPIV, V.M.; ZATORSKII, R.A. $m$-submultisets and $m$-permutations of multisets elements. Carpathian Mathematical Publications, [S. l.], v. 13, n. 1, p. 240–258, 2021. DOI: 10.15330/cmp.13.1.240-258. Disponível em: https://scijournals.pnu.edu.ua/index.php/cmp/article/view/4693. Acesso em: 22 may. 2024.